Wellbore flow control valve and method

This application is a National Stage application of PCT/CA2022/050597, filed Apr. 20, 2022, which claims the benefit of U.S. Provisional application No. 63/180,750 filed on Apr. 28, 2021, the entire contents of which are incorporated herein by reference.

Embodiments taught herein relate to apparatus and methods for use in wellbore completion operations and, more particularly, to downhole sleeve valves.

In staged wellbore completion operations, a formation is divided into multiple zones that are treated in isolation. Conventional sleeve assemblies are used to selectively establish communication between a bore of a tubular string, such as a casing string or completion string, extending along a wellbore and the wellbore. Each sleeve assembly comprises a tubular housing fit with a sleeve. The sleeve assemblies are typically spaced along the casing string and are configured to permit the flow of fluids through ports of the tubular housing when the sleeve is shifted axially to an open position to expose ports in the housing or to block the flow of fluids therethrough when the sleeve covers the ports in a closed position.

When zones do not need to be closed after opening, open-only sleeve assemblies may be used. These sleeve assembles are run-in-hole with the sleeves initially in a closed configuration, wherein ports in the housing of the sleeve assemblies that allow fluid communication from the production string to the wellbore are blocked by the sleeves. During treatment, the sleeves are shifted to an open configuration, wherein the ports in the housing are exposed. These sleeves are commonly ball-actuated, wherein a ball introduced into the casing string at surface engages a seat of the corresponding sleeve. The pressure in the casing bore can then be increased to shift the sleeve downhole, such as with downhole fluid pressure.

To provide the capability to open sleeve assemblies at particular zones of interest along the wellbore, the seats of the sleeves can be varied to correspond with the zones of interest. The sleeve assemblies can be arranged such that those having the smallest diameter seat are located at the lower portion of the well, and the seats of the sleeve assemblies increase in diameter toward surface. To actuate the sleeve controlling communication with the zone of interest, a ball having a size corresponding to the seat of the sleeve can be introduced. The ball proceeds downhole from surface and bypasses the larger seats of those sleeve assemblies uphole of the sleeve of interest, and is seated on the seat of the sleeve of interest. Pressure in the casing bore can then be increased to actuate the sleeve of interest to expose the ports thereof and establish communication with the zone of interest.

It is also known to provide multiple consecutive sleeve assemblies having equal sized seats to be actuated with the same ball. The seats of the sleeve assemblies can be configured to permit the ball to continue to travel therethrough after the sleeve has been actuated to the open position. The seat of the most downhole sleeve of the series can be configured to retain the ball thereon. In this manner, the series of sleeve assemblies can be opened such that a zone of interest can be treated through multiple sleeve assemblies at once.

Further, it is known to provide burst discs or plugs in the ports of the sleeve housings configured to rupture, shatter, or otherwise be removed at a predetermined threshold bore pressure so as to permit flow through the ports. In this manner, a series of sleeve assemblies can be actuated to the open position using casing bore pressure without loss of fluid pressure through the exposed ports of sleeve assemblies uphole. When the threshold bore pressure is reached, the burst discs of the sleeve assemblies of the series are ruptured, such that treatment fluid can then flow through the ports of the sleeve assemblies of the series substantially simultaneously.

U.S. Pat. No. 8,215,411 to Flores et al. (“Flores”) discloses a cluster opening sleeve apparatus and method using ball-actuating shifting sleeves, wherein ports have insets with small orifices that produce a pressure differential to help shift the sleeves. Flores teaches that these insets are removed with a threshold bore pressure once the sleeves have shifted.

U.S. Pat. No. 9,297,241 to Arabskyy (“Arabskyy”) discloses a fracturing tool and method using a sliding sleeve assembly with burst plugs installed in fluid ports to conceal the fluid ports prior to shifting. Said burst plugs are also shattered or removed by a requisite bore pressure after the sleeves have been shifted to the open position.

Flores and Arabskyy both teach the use of insets or plugs in the ports in the outer housing of the corresponding sleeve assemblies. As the insets are exposed to the irregular surface of the wellbore when the sleeve assemblies are run-in-hole with the casing string, they are susceptible to contamination or damage. Such damage can cause leakage of fluid from the casing bore into the wellbore, or failure of the insets before the predetermined pressure is reached. A failure of this type may be difficult to detect until operations have commenced and may render the casing string inoperable, requiring replacement of the entire casing string.

Additionally, to prevent or mitigate the buildup of debris (e.g. rocks or cement) in the sleeve housing ports and inset nozzles, a protective layer of cement inhibiting grease can be located in the ports with a thin membrane thereover to prevent said grease from being displaced. However, such covering is typically easily ruptured and said grease would similarly be exposed to the adverse conditions of the wellbore as the casing string is run-in-hole.

There is interest in the oil and gas industry for sleeve assemblies that provide more reliable protection to fluid treatment ports prior to opening thereof for treatment.

The disclosure provides a sleeve assembly having a sleeve housing with flow ports and a shifting sleeve slidably retained therein and having corresponding treatment ports. When the sleeve assembly is in a closed configuration, the body of the sleeve blocks the flow ports and the treatment ports are misaligned with the flow ports. When the sleeve assembly is in an open configuration, the treatment ports of the sleeve align with the flow ports of the sleeve housing, allowing fluid communication to the formation. Correspondingly, when the sleeve assembly is in the closed configuration, the treatment ports are protected from and against fluid, debris, and rough surfaces in the wellbore by the body of the housing.

In the present disclosure, insets are placed in the treatment ports and are not exposed to the formation as the sleeve assembly is run-in-hole with the sleeve in the closed position, thus mitigating potential damage to the insets. In some embodiments where the inset is a burst disc, the burst discs are protected from wellbore pressure and potential inadvertent rupture/activation when the sleeve is in the closed configuration, as the inset is protected from the formation when the sleeve is in the closed configuration. In some embodiments wherein the inset is dissolvable, the insets are not exposed to water or other fluids in the wellbore prior to shifting the sleeve assembly to the open configuration.

In a broad aspect, a sleeve assembly for controlling communication with a downhole formation includes a sleeve housing, a sleeve and a seat. The sleeve housing has a housing bore and one or more flow ports. The sleeve is retained slidably in the housing bore and has a sleeve bore and one or more treatment ports. The sleeve is slidable from an uphole closed position, in which the one or more flow ports are blocked by the sleeve, to a downhole open position in which the one or more flow ports are at least partially aligned with the one or more treatment ports. The seat is disposed in the sleeve bore, configured to extend at least partially into the sleeve bore to receive an actuating member. The sleeve also has one or more inset members disposed in each of the one or more treatment ports.

In an embodiment, the inset members are burst discs of a frangible material for at least temporarily maintaining fluid pressure in the sleeve bore and configured to be removed once the fluid pressure reaches a threshold pressure.

In an embodiment, the inset members are at least partially dissolvable material.

In an embodiment, the inset members are non-dissolvable nozzles.

In an embodiment, the inset members are a dissolvable material surrounding the non-dissolvable nozzle and the inset member is removable from the treatment port when the dissolvable material dissolves.

In an embodiment, the sleeve defines one or more radial grooves in the exterior surface of the sleeve straddling the one or more treatment ports with sealing members positioned therein.

In an embodiment, the housing defines one or more radial grooves in the housing bore straddling the one or more flow ports and having sealing members positioned therein.

In an embodiment, the seat is actuable between a first condition wherein the seat retains an actuating member and a second condition wherein the seat is adapted to deform to allow the actuating member to pass through the sleeve bore.

In an embodiment, the seat is in the first condition when the sleeve is in the uphole closed position and in the second condition when the sleeve is in the downhole open position.

In an embodiment, the actuating member is one of a ball, a plug, or a dart.

In an embodiment, the sleeve is temporarily retained in the uphole closed position using a retainer.

In an embodiment, the retainer is a shear screw or retaining pin.

In an embodiment, the sleeve housing has an annular overhang defining an annular protection pocket configured to receive at least a portion of the sleeve when the sleeve is in the uphole closed position, such that the one or more inset members are located in the protection pocket.

In an embodiment, sealing members are positioned on one or both of the sleeve and sleeve housing to fluidly isolate the one or more inset members in the protection pocket when the sleeve is in the uphole closed position.

In a broad aspect, a method of treating a zone in a formation accessed with a completion string having one or more sleeve assemblies therealong includes introducing an actuating member into the completion string to engage a seat of a target sleeve assembly of the one or more sleeve assemblies, actuating the target sleeve assembly from an uphole closed position to a downhole open position with the actuating member engaged in the seat to at least partially align one or more treatment ports of a sleeve of the target sleeve assembly with one or more flow ports of the target sleeve assembly, increasing fluid pressure in the completion string to a threshold pressure to burst inset members disposed in the one or more treatment ports, and treating the formation through the aligned treatment ports and flow ports.

In an embodiment, the step of actuating the target sleeve assembly to the downhole open position further includes removing the one or more treatment ports of the sleeve from a protection pocket of the target sleeve assembly.

In a broad aspect, a method of treating a zone in a formation accessed with a completion string having one or more sleeve assemblies therealong includes introducing an actuating member into the completion string to engage a seat of a target sleeve assembly of the one or more sleeve assemblies, actuating the target sleeve assembly from an uphole closed position to a downhole open position with the actuating member engaged in the seat to at least partially align one or more inset nozzles in one or more treatment ports of a sleeve of the target sleeve assembly with one or more flow ports of the target sleeve assembly, and treating the formation through the inset nozzles of the aligned treatment ports and the flow ports.

In an embodiment, the inset nozzles are at least partially made of a dissolvable material, and the step of treating the formation further includes dissolving the dissolvable material, and producing fluid from the formation through the aligned treatment ports and flow ports once the dissolvable material has dissolved.

In an embodiment, the step of actuating the target sleeve assembly to the downhole open position further includes removing the one or more treatment ports of the sleeve from a protection pocket of the target sleeve assembly.

The present disclosure relates to sleeve assemblies located along wellbore casing extending through a subterranean formation for controlling fluid communication between a bore of said casing and select targeted zones, or zones of interest, of the formation. Said communication is established through one or more flow ports formed in a housing of the sleeve assemblies and corresponding treatment ports in a sleeve of the sleeve assembly when in an open position.

Ports that are exposed to the formation while the casing string is run-in-hole are susceptible to plugging by debris. It may also be desirable to prevent fluid flow through the ports even when the sleeve assembly has been actuated to the open position, and only permit fluid flow therethrough once a requisite threshold bore pressure has been reached. As a result, sleeve assemblies may include inset members within the ports that are broken, ruptured, or otherwise removed in response to the bore pressure reaching the predetermined level. However, these inset members themselves are exposed and are susceptible to damage when the casing string is run-in-hole. The present disclosure teaches an apparatus wherein inset members are protected when the casing string is run-in-hole.

Referring to, an embodiment of a sleeve assemblycomprises a generally tubular sleeve housingand a generally tubular sleeve. Referring to, the sleeve housingdefines a housing boreextending axially therethrough and one or more radial flow ports. The housing boreis in communication with the bore of the casing string. The one or more flow portsprovide fluid communication between the housing boreand the exterior of the housing. The housing boreis designed to slidably retain the sleevetherein, and permit it to actuate between at least between an uphole closed position and a downhole open position.

The sleevedefines a sleeve boreextending axially therethrough and one or more radial treatment ports. The one or more treatment portsprovide fluid communication between the sleeve boreand an exterior of the sleeve. In some embodiments, the one or more treatment portscorrespond in size and position to the one or more flow ports, and are at least partially aligned therewith when the sleeveis in the downhole open position.

In some embodiments, annular sealscan be provided in seal groovesdefined in an exterior surface of the sleeveor in the housing boreand straddling the flow portsfor fluidly sealing between the housing boreand the sleevewhen the sleeveis in the downhole open position such that in the downhole open position, the annular sealsassist in ensuring that fluid in the sleeve boreflowing through the treatment portsflow through flow portsand not through the space between the housing boreand the sleeve. Similarly, annular sealscan be provided in seal groovesdefined in the exterior surface of the sleeveor in the housing boreto straddle the flow portswhen the sleeveis in the uphole closed position. In this manner, fluid in the sleeve boreor housing boremay be prevented from leaking out of the sleeve assemblyvia the treatment portswhen the sleeveis in the uphole closed position.

As shown in, in some embodiments, the housingcan further comprise an annular overhangforming a protection pocketfor receiving a portion of the sleevecontaining the treatment portswhen the sleeveis in the uphole closed position. In some embodiments, seals,can be located in the protection pocketto further protect the inset membersfrom contact with fluids, being washed out, or eroded when the sleeveis in the uphole closed position, thereby protecting inset memberslocated in the treatment portsas described in greater detail below. For example, the seals,can be located in the outer and/or inner walls of the sleeveand configured to be located within the protection pocketwhen the sleeveis in the uphole closed position. The seals,can also be located in the interior walls of the protection pocket, or both the sleeveand the interior walls of the protection pocket.

With reference to, the sleevefurther comprises a seatconfigured to interact with an actuating member. The seatis configured to engage and restrict movement of the actuating memberthereby. In the depicted embodiment, the seatis located downhole of the treatment ports. In some embodiments, the actuating memberis a ball, a plug or a dart configured to be temporarily retained by the seatduring which time it substantially obstructs fluid flow through the sleeve bore. An example of a suitable actuating memberis the actuating device disclosed in Applicant's PCT patent application no. PCT/CA2019/051054, incorporated herein in its entirety.

Referring still to, the sleeve assemblyis shown with the sleeveat the uphole closed position, wherein the one or more treatment portsof the sleeveare not aligned with the one or more flow portsof the housing. In the uphole closed position, the one or more flow portsare blocked by the body of the sleeve, obstructing fluid communication between the sleeve boreand the formation. When an actuating membercorresponding to the sleeve assemblyis introduced into the casing bore from surface, fluid pressure and/or gravity pushes it through the casing bore until it engages with the seat, thereby obstructing fluid flow through sleeve bore. At this point, fluid pressure can be adjusted to a threshold level to actuate the sleevetoward the downhole open position. Referring to, in the downhole open position, the one or more treatment portsof the sleeveare at least partially aligned with the corresponding one or more flow portsof the housing, allowing fluid communication between the sleeve boreand the formation.

Referring to, in an embodiment, the seatcomprises a plurality of seat retaining membersdisposed in corresponding seat slotsin the sleeve. In an embodiment, the housing borefurther comprises an annular groovelocated downhole of the seatwhen the sleeveis in the uphole closed position, and axially aligned with the seatwhen the sleeveis in the downhole open position. In such embodiments, the seat retaining membershave a radial thickness greater than a thickness of the sleeve. In the uphole closed position, the portion of the seat retaining membersdistal the center of the sleeve boreengages the interior walls of the housing bore, resulting in a portion of the seat retaining membersprotruding into the sleeve bore. The corresponding actuating memberis configured to pass through sleeve boreand engage with the protruding seat retaining memberswhen the sleeve is in the uphole closed position. With the actuating memberengaged with the seat, fluid flow is obstructed through sleeve bore. With fluid flow obstructed, fluid pressure can be increased to provide a downhole force on the sleeveeffected through the actuating memberand the seat. Once a specified pressure threshold is reached, the sleeveis shifted from the uphole closed position to the downhole open position.

The movement of the sleevecan be limited at an uphole end of the housing boreby an uphole shoulderand at the downhole end of the housing boreby a downhole shoulder or ramp. As shown in, when the sleeveis in the downhole open position, the seat slotsalign with the annular groove, resulting in the seat retaining membersradially retracting from the sleeve boreinto the annular groovesuch that they clear the sleeve bore, and allowing the actuating memberto pass through the now-unobstructed sleeve boreand the housing boredownhole to a subsequent sleeve assembly.

In alternative embodiments, another type of deformable seatmay be used which retains the actuating memberthereon when the sleevein the uphole closed position, and permits the actuating memberto proceed downhole thereby when the sleeveis in the downhole open position.

In other embodiments, the seatcan simply be an annular constriction in the sleeve boreconfigured to engage a corresponding actuator. The annular constriction cannot radially retract, such that the actuatoris permanently seated on the seatonce engaged therewith, and is removable via methods such as milling out, reverse circulation, or dissolving.

In some embodiments, a series or cluster of sleeve assembliescan be configured to be actuated by a single actuatorby configuring the seatsthereof to be retractable or deformable, as described above, and to have the same dimensions corresponding with said actuator. In this configuration, the actuatorcan engage a most uphole assemblyof the cluster to actuate it to the open position upon application of sufficient bore pressure, then proceed further downhole to the next assemblyof the cluster after the seatof the most uphole assemblyis retracted or deformed. A most downhole assemblyof the cluster can have a non-retracting/deformable seat, such that the actuatoris not permitted to proceed further downhole after engaging therewith.

Referring to, in an embodiment, the sleeveis held in the uphole closed position using a retainer. In some embodiments, the retaineris a shear screw, a shear pin or a detent member such as a collet engaging a slot or groove. The retainercan be configured to require a requisite shifting force to overcome said retainerand shift the sleeve.

Once in the sleeveis in the downhole open position, friction and the direction of fluid flow will generally keep the sleevein the downhole open position. However, a downhole retainersuch as a second detent member can be used to retain the sleeve in the downhole open position. The second detent member can also be provided at other locations where the sleeveand housingcontact in the downhole open position to retain the sleevein the open position.

Referring to, in some embodiments, an inset memberis disposed in each of the one or more treatment ports. In some embodiments, the one or more inset memberstemporarily obstruct fluid flow through the one or more flow ports. When the sleeveis in the uphole closed position, the inset membersare protected from fluid flow in the wellbore and exterior of the sleeve assembly, which protects the inset memberswhen the sleeve assemblyis run-in-hole and keeps the inset memberin place as fluid pressure builds up. When the sleeveis moved to the downhole open position, the treatment portsalign with the flow ports. When the seatof the sleeve assemblyis engaged with the actuating member, the sleeve boreis blocked and the pressure differential between the fluid in the sleeve boreand the formation is exerted on the inset members. In an embodiment, the inset membersare designed to temporarily maintain fluid pressure in the sleeve bore and to shatter, rupture, or otherwise be removed from the treatment portsat a threshold pressure. The specific threshold pressure depends on the specific characteristics of the inset membersand how they are secured in the treatment ports, which can be selected to provide the desired threshold pressure.

In an embodiment, the inset memberis a burst disc comprised of a suitable material such as a frangible material. Examples of such materials include an alloy, ceramic, or glass. The inset memberis secured in the treatment portand is designed to rupture, shatter, or otherwise clear the treatment portin response to the casing bore reaching the threshold pressure. In some embodiments, the threshold pressure is between 500 to 2,500 pounds per square inch.